Biogas, solar power N.J. wastewater treatment plant

A northern New Jersey wastewater treatment plant is using a combination of biogas and solar energy technologies to produce 100 percent of its power requirements.

Through a 20-year, public-private partnership with Natural Systems Utilities, Middlesex Water Co. and American Refining and Biochemical, the village of Ridgewood, N.J., recently brought the biogas energy project on line.

At the Ridgewood Wastewater Treatment Plant, methane produced via anaerobic digestion (AD) of wastewater sludge is being used to power a 240-kilowatt engine generator. The electricity produced will power the wastewater plant according to Christelle Bruneau, manager of business development and marketing for Natural System Utilities. “All power will be used on site with a net meter to the grid to monitor the excess electricity produced,” she said.

To further increase the plant’s energy efficiency and independence, waste heat from the engine is being used to heat the digester units to facilitate the AD process. In addition, solar arrays were installed at four different locations to produce additional electricity for Village facilities.

The treatment plant upgrades were designed and built by the project partners under joint venture Ridgewood Green RME LLC, which owns the newly constructed additions. The facilities are being operated by village employees in concert with Ridgewood Green RME.

In addition to cost savings from the Village utility bill, additional income is being generated by selling the higher value solar and biogas renewable energy certificates and purchasing lower cost Green-e Certified National RECs to maintain the plants reliance on 100% renewable energy. NSU, MWC and ARB worked with several key partners on various components of the project including Bio-Organic Catalyst Inc., which provides optimization of the anaerobic digestion process with addition of an enzyme product which increases biogas production, HDR-HydroQual Engineers, which provided engineering design services and construction assistance for the project, and Advanced Solar Products, which provided turn-key installation of the solar panels.